From Information
Dissemination
While discussion continues on the CIG,
there is much less talk on the imminent introduction of the largest naval gun
to enter active U.S. naval service since the Second World War. The 155mm Advanced Gun System (AGS) has undergone
development since the early 1990’s as a component armament of the SC-21 family
of warships. During this “high noon” of the American “unipolar moment”, there
was much more attention toward achieving long-range, coordinated “fires” than
concern about the sea control that made such activities viable. How effective
can an AGS with a nominal range of 24 nm (nautical miles) for conventional
shells and 63 nm for advanced long range land attack projectiles (LRLAP) be in an environment of
advanced anti-access/area denial (A2AD) capabilities? The AGS is perhaps useful
in attacking isolated locations outside an opponent’s home littoral and in the
later stages of a conflict when an enemy A2AD system is significantly
degraded. The DDG 1000 had few direct threats when first conceived and if
employed close to shore as demanded by the range of its main battery guns, any
gain in stealth from the ship’s tumblehome hull form will be offset by the
danger of visual detection. The ship does have some formidable strike and
defensive capabilities through its vertical launch system (VLS) mounted
missiles and AN-SPY-3 radar system. It remains to be seen, however, if those
capabilities justify deploying the ship on the front lines at the outset of a
high-end conflict. The DDG 1000 is dominated by the AGS that can only be
employed at the present time against land-based targets.
The Daily Beast article and others have
discussed questions of the ship’s tumblehome (inward curving) hull form and
stability in rough seas. The tumblehome hull was a familiar feature of many
warships at the end of the 19th and the beginning of the 20th
century. French, Russian, and some American warship designers embraced it
as a way of creating greater freeboard (height from water line to deck), better
sea-keeping, and from these together, improved gunnery. The tumblehome hull's
inward curve from the waterline to the main deck causes a reduction in reserve
buoyancy, the amount of the ship outside of the water. Freeboard is the
physical factor that allows steel ships to remain afloat. A small reduction in
reserve buoyancy, especially if received off the center
line
of the ship in the form of flooding from battle damage or fire-fighting efforts
could cause a sudden loss of stability and rapid sinking. The ship's reliance
on automated damage control systems, combined with reduced reserve buoyancy
could be a problem in the case of significant flooding. Warship designers began
to view the tumblehome hull as suspect after the Russo-Japanese War when
several Russian warships with that feature capsized and sank quickly after only
moderate damage. The feature was discarded wholesale after the First World War
saw significant casualties in French warships with the unconventional hull
form. The Bouvet (shown in above photo) struck a small mine (176 lbs) and sank
in less than two minutes.
Despite these possible problems with its
main armament and hull form, the DDG 1000 represents a return to a number of
positive features and notable firsts worth further exploitation and
development. The ship's electric drive system is the first for a U.S. “capital”
warship since turbo-electric propulsion systems were installed on the U.S.
aircraft carriers Lexington and Saratoga in the late 1920’s.
These units were so capable that Lexington's powerplant was able to
provide 25% the city of Tacoma, Washington's electricity in 1929/1930 after
extreme drought conditions made hydroelectric sources in area useless. Turbo-electric power proved to be a very fuel
efficient system and extremely robust in combat. Both ships sustained
significant damage during World War 2, and although Lexington was
sunk at the Battle of the Coral Sea in May 1942, the ship's turbo-electric
drive system remained operational until spreading fires made the ship
untenable. The DDG 1000’s similarly large electric power plant is the first
step toward fielding directed energy weapons at sea. These include
electromagnetic rail guns with greatly increased range that may replace the AGS
currently fitted. The AN-SPY 3 radar represents a significant advance in
detection, and air and missile defense capabilities, especially in congested littoral
areas. The 155mm gun still has a part to play. It has surface warfare potential
if converted to a dual purpose land/surface attack weapon. While perhaps an
interim step in the direction of a rail gun, the AGS could also play a useful
anti-surface role. The main battery of the DDG 1000 could quickly smother an
enemy warship in a barrage of 155mm projectiles from 24nm to 60+ nm. Defense
against artillery and mortar shells is possible, as demonstrated by the U.S.
Centurion Gun System,
but it is not a capability currently found on the warships of potential
aggressors. Experience from the employment of the AGS as a surface gunnery
weapon is again also a step toward use of a railgun as anti-surface weapon with
estimated ranges between 110 and 220nm.
Potential operational and damage control
issues aside, the DDG 1000 represents a good investment in future capability.
It could be altered enough to make the ship a viable addition to a
post-Post-Unipolar U.S. fleet. Enabling the 155mm AGS as a surface weapon would
expand U.S. anti surface warfare capabilities and force opponents to spend
money to undertake defensive measures against artillery shells. One or more of
the ships could be altered (if stability conditions permit) as prototype
cruiser platforms optimized for anti-air/missile defense by removing one AGS
and substituting greater missile armament in its place. The ship’s stability
after receiving damage remains a concern, especially as it relies on an
automated damage control system to provide much of the immediate response to
the effects of weapon strikes. The composite material deckhouse of the first 2
units, as opposed to the steel version on the third and final unit of the class
represents an additional vulnerability. All such shortcomings, however, may be
more effectively addressed if they are acknowledged as such. No warship is
perfect and each represents a series of choices. The choices available to
designers in the late 1990s are different from those that must be considered in
the present. The DDG 1000 class represents a welcome addition to the fleet in
that the technologies and capabilities they possess will likely be core
components of the fleet of 25 years hence. Together they might form a valuable
“squadron
of evolution”
for the 21st century and be useful elements in exercises and
wargames.
The famous naval author Joseph Conrad
described the actions of an isolated warship conducting naval bombardment against
unseen targets at the beginning of his most famous novel The Heart of
Darkness. In it, his narrator Marlowe describes a French cruiser shelling
unseen enemies ashore as follows:
“Once,
I remember, we came upon a man-of-war anchored off the coast. There wasn't even
a shed there, and she was shelling the bush. It appears the French had one of
their wars going on thereabouts. Her ensign dropped limp like a rag; the
muzzles of the long six-inch guns stuck out all over the low hull; the
greasy, slimy swell swung her up lazily and let her down, swaying her thin
masts. In the empty immensity of earth, sky, and water, there she was,
incomprehensible, firing into a continent. Pop, would go one of the six-inch
guns; a small flame would dart and vanish, a little white smoke would
disappear, a tiny projectile would give a feeble screech—and nothing happened.
Nothing could happen. There was a touch of insanity in the proceeding, a sense
of lugubrious drollery in the sight; and it was not dissipated by somebody on board
assuring me earnestly there was a camp of natives—he called them
enemies!—hidden out of sight somewhere."
The
original design of the DDG 1000 may have evoked a similar image of unimpeded
naval surface fire support, but the unrestricted sea control that Conrad’s
imagery conjures up is no longer a reality in the second decade of the 21st
century. While perhaps not designed for such conditions, the DDG 1000 still has
a significant role to play in the present as both a technology demonstrator and
as a surface warship. The specter of its guns may yet haunt future opponents
and it’s all-electric heart power future weapons of greater capability and
effectiveness.
No comments:
Post a Comment